Burglar alarm



Feb. 5, 1935. J. E. CLARK BURGLAR ALARM Filed Oct. 18, 1929 2 Sheets-Sheet 1 INVENTOR. Jake; 1?. 6443A A TTORNE Y.

Feb." 5, 11%35. E CLARK BURGLAR ALARM Filed Oct. 18, 1929 2 Sheets-Sheet 2 INVENTOR. (fa 7:; 6200K A TTORNE Y.

Patented F cl). 5, 1935 BURGLAR ALARM James E. Clark, Detroit, Mich, assignor to Wilson H. Sterling, Detroit, Mich.

Application October 18, 1929, Serial No. 400,625

for

lit);

2 Claims.

the object thereof is to provide a comparatively simple and inexpensive device adapted to be positioned either within a building or exteriorly thereof through and by means of which the entering of the building or tampering with safes or other containers for valuables by unauthorized persons establishes an electric circuit to thereby cause the device to fire a number of blank cartridges in succession and at the same time actuates' another type of alarm or signal.

Previous devices have provided a cartridge firing' mechanism of some character but the feature and objectof this invention is to provide an elec trically controlled mechanism through energization of which a mechanically operated device releases a hammer to, strike afiring pin and thus explode the cartridges after the manner of that of an. ordinary firearm, and a feature of the construction is involved in the provision of a cartridge container that is movable from, firing relation with the firing pin to permitready removal or introduction of cartridges and that may be secured in firing relation therewith.

A further object. and feature of the invention.

is involved in the provision of a series of weights slidable on standards, the first of the group of weights normally being sustained in place by an el'ectro-magnet and the remainder of the group being provided with a latch tending to hold the same in normal position ready for operation, the arrangement of the latches being such that the dropping of the first weight releases the latch member retaining the second weight and the dropping of the second weight releases the latch member retaining the next and so entire group.

By such an arrangement of the parts the 'electrical elements of the apparatus are reduced to the greatest simplicity not requiring switches or movable parts in the electric circuit liable to get out of order or cause trouble in operation as merelya breaking of the current supply to the magnet will result in a discharge of the entire group of cartridges mechanically.

Another feature of the invention is involved in the construction of the weights and standards to prevent too rapid successive firing of the cartridges. This is accomplished by so constructing these parts that a predetermined time interval in the releasing of the successive weights is secured in order that the cartridges will be fired at timed intervals corresponding to the firing of a revolverwhereby the attention of passersby or persons within the sound of the fired cartridges on for the will be attracted and they will realize that an unusual condition exists within the building.

The invention further is of such character as to permit its use in any structure such for instance as a safe or other device which it is desired to protect from unauthorized entrance and while cartridges are shown as being the preferred form of signal actuated in succession the mechanism through and by means of which the cartridges are fired in the construction shown may be applied to any form of signal device which is actuated or released to actuation by the weights caused to drop successively to trip the mechanism holding the signal in set condition.

These and other objects and various novel features of the invention are hereinafter more fully described and claimed, and the preferred form of construction of an alarm or signal device embodying my invention is indicated in the accompanying drawings in which- Fig. 1 is an elevation partly in section showing my improved signal device.

Fig. 2 is an enlarged section taken on line 2-2 of Fig. l.

Fig. 3 is an end view taken from the left side of. Fig. 1 showing the enclosing case in section and a weight in its set position.

Fig. 4 isa similar view showing a weight in its dropped position and the signal mechanism actuated.

Fig. 5 is a detail in section of a weight and portion of its standard showing the means for retarding its movement downward in the release of a signal actuating mechanism.

In the preferred embodiment of the invention a casing 1 is provided within which the mechanism is housed. The front 2 of this case may be in hinged relation to permit ready access to the interior of the case for the setting of the alarm and the introduction or removal of the cartridges as the case may be. Within the case is a bracket 3 fixedly secured by a downwardly extending flange 4 to the rear wall 5 of the casing or cabinet.

At its forward end the bracket 5 has secured thereto or integrally formed therewith, as here shown, a block 6 having a. series of vertically positioned recesses 7 opening through the lower face 8 of the block 6 by a small central aperture 9. This recess at its upper end is covered by a plate 10 which may be secured in place in any convenient manner as by means of screws 11 at its opposite ends or intermediate the chambers 7. In each chamber 7 is what may be termed the hammer which consists of a rod like portion 12 and a lower hammer end 13 of greater diameter. A coiled spring 14 of the proper tension is introduced between this enlarged end 13 and the plate 10 in the construction shown, and when compressed by the raising of the hammer upwardly to position shown in Fig. 2 the hammer is under such tension as to cause the same to strike the firing pin 15 with sufficient force to fire the cartridge. The firing pin has a pointed end 16 positioned the aperture 9 and enlarged head 17 adapted to be engaged by'theend 13 of the hammer. The upper end of the rod 12 of the hammer is pivoted to a lever 18, the end 19 of which extends forwardly of the block 6 -and the opposite end 20 of which extends to the rear of the block. The lever l8f'is formed with a slot" 21 therein through which extends a pin 22 on a standard 23 secured to the bracket.- The terminal end of the portion 20 engages beneath the hook end 24 of the pivoted latch 24 as shown in Fig. 2, this latch being pivoted between ears of ablock 25 provided on the bracket This lever 24 has a rearwardlyextending part 26 bifurcated to pass on opposite sides of a vertical shaft or standard 27 secured to the base.

A coiled spring 28 is placed under compression the positioning of the lever 24 as shown in Fig.-

2. 'A peculiarity of this construction is in the provision of an upwardly'extendmgrod 29 having an end portion extending horizontally through the earedblock 25 and through the latch member 24 to which the latch member is fixed. the turning of the latch" member 24 in the eared block 25 moves the rod portion 29 correspondingly. On 7 the rod 27 about which the bifurcated end 26 of the latch member 24 extends is a sleeve3l and also on this rod is a weight 32 preferably of cylindrical form and having a cylindrical aperture riding on a standard or rod 27. Positioned in'the casing above the upper end of the rod '27, as will be understood from Fig. 1, is an electro-magnet 33' having the circuit wires 34 and 35. When the circuitis energize-d, theiron weight 32 may be raised to position to come within the influence of the magnetized core of the magnet which will hold position and, when. the circuit is the same in I the magnet thus deenergized the broken and weight is released to fall by gravity on the rod 27 and, at the completion of its downward move ment, strikes the sleeve 31 depressing the end 26 of the lever 24 withdrawing the hook end 24* thereof from engagement with the end 20 of the lever 18 therebyrelea'sing the hammer to actuation by the spring 14. The'striking of the firing pin by the hammer dischargesa cartridge. In turning the hooked lever 24 by downward movement of is moved backwardly. a

The upper end of the rod 29 has an outturned upper end 36 which lies beneath a second weight 37 and. by the backward movement of the rod 29 through turning the lever 24, the end 36 is withdrawn from beneath the weight 3'7 allowing it to fall by gravity. Inasmuch as there are hammer mechanism, levers and latch members for each of the weights utilized, the weight 37 releases alatch similar to the member 24 to thereby operate the next rod'38 and release a weight 39 which in turn operatesasucceeding rod 40 to release the weight 41 of the series here shown. Obviously a greater or less number of weights and operating devices may be used.

The cartridges to be fired are preferably carried by ablock 42 which is normally positioned beneath the block 6 of the bracket This the weight, the rod 29, to which the lever 24 is secured on the horizontal portion 30 thereof,

block 42 has aseries of apertures 43 therein ar- [similar link 46 pivoted to the opposite end thereof, the lower end of which is slotted to receive a 47'shown in Fig. 3. The outer end of the pin is threadedto receive a wing nut 48, and it is to be understood that each end of the block 42 is provided with a similar pin 47 and wing nut 48. By releasing these wing nuts 43 the block 47 "may be moved laterally outwardly when the door 2v is open to the position shown in dotted lines in Fig. 4 permitting removal of the fired cartridges or introduction of new cartridges and when moved to position shown in full lines asshown in Figs. 2, 3 and 4 the respective cartridges are placed in firing relation with the'respective firing" pins in the aperture 7 of the block 6. It is desirable oftentimes that a continuous alarm be given through the operation of this device and this may be actuated simultaneously with the firing of the cartridges or subsequent to, the firing-of the same or at some interval between the firing of the first and last cartridges as may be found desirable. A convenient continuous signal is indicated in Fig. 1 as being an electric bell 50 in a circuit formed of wires 51 and 52 and a switch 53 for this circuit is provided onthe bracket 3, the switch havinga press buttoni54'to close the circuit as will be readily understood, The closing means for the circuit is a bar 55 here shown as being provided on the first weight 320i the series and extending to one side thereof which, as the weight falls, engages the button 54 and closes the circuit through the bell. The bell will therefore sound during such interval as the weight 32 is in its down position. Manifestly, the switch may be positioned ina similar relation to any one of the weights shown and thus the time at whichthe continuous signal is actuated may be varied. l J I t While the bell is the preferred form of signal other forms of signal may be utilized it being within the spirit and scope of this invention to introduce any form'of electrically energized signal apparatus in the circuit 51 and 52 to be closed by a switch similar to that shown. For instance, this circuit'51 and 52 gives a signal at a remote point as for instance a central station and conveniently the first or last, of the series of weights 39 and 41 for the weight 32. In Fig; 1 these standards 37*, 39

and 41 are rod-like in form'similar to the mem-' ber 27 and with suchan arrangement of the standards and smooth aperture for the respective weights theseweights will" drop rapidly pro-' viding a very small interval of time between the firing of the same. Preferably, in order that the firing of the cartridges may not be too rapid to cause the impression of there being successive shots fired from a revolver, it is necessary to delay the movement of the weights 3'7, 39 and 41 to provide the necessary time interval.

This may be accomplished by the construction shown in Fig. 5 in which a rod 30 for instance corresponding to the rod 37 of Fig. 1 is formed with a spiral groove 60 and the weight 3'? corresponding to the weight 37 of Fig. 1 is provided with a pin 61 riding in the spiral groove. By this construction and upon release of the latch rod 36, the weight While falling by gravity is retarded in its fall by necessity of its revolution about the rod 30 caused by the pin 61 traversing the spiral groove. This spiral may be of greater or less pitch depending upon the time interval desired and the distance through which the weight is to fall but by such arrangement the time interval between the firing of successive cartridges may be determined.

After the cartridges have been fired and the cartridge block 42 moved to the position shown in dotted lines, the fired cartridges are removed and a new charge placed therein. The hammers may be reset by hand for which purpose the forwardly extending portion 19 of the lever 18 is provided. By lifting up on this end 19 of the lever 18, the end 20 may be introduced beneath the hook end 24 of the latch 24. This releases the firing pins from pressure of the spring 14 and will permit the reintroduction of the cartridge container 42 to position shown in full lines in Figs. 3 and 4. It is desirable that apertures shown by dotted lines 70 in Fig. 1 be provided in the bottom wall 71 of the casing in registration with the apertures for the cartridges in the block 42. By such arrangement the exploded charge is discharged to atmosphere.

Upon reestablishment of the circuit the weights may be raised successively to their set positions, the first weight 32 upon energization of the circuit being held by the magnet and the latches for the next weights positioned in succession to hold the respective weights whereupon the device is ready for subsequent operation.

No attempt has here been made to show the relationship of the circuit relative to a door or window opening or other element that may be moved to break the circuit. It is commonly known in this art that the circuit is so positioned relative a building, compartment, safe or other device that the unauthorized movement of some portion of the guarded structure breaks the circuit as by the breaking of a contact directly or through operation of a switch or any of the well known means now commonly utilized in circuits of this character.

The above description has been concerned principally with the use of the invention as a burglar alarm in which case the firing of the cartridges is the preferred function of the spring-pressed elements 12 but it will be readily understood that the invention is not confined to the firing of a cartridge as a signal of any desired character may be actuated through movement of the member 12 upon release through the dropping of these weights in succession.

It is believed evident from the foregoing description that the device is simple and inexpensive in construction and is unique in character and arrangement of the several of the component elements, particularly the means for securing the successive actuation of the signaling devices here indicated as cartridges to be fired, and that, simultaneously or at any period before or after the firing of the cartridges or actuation of other types of signals that may be used in place thereof, a continuous alarm may be given or an alarm given at a remote point through and by means of the circuit 51 and 52 closed by movement of a weight by gravity. It will further be observed that the various objects of the invention are attained by the construction described.

Having thus fully described my invention, its utility and mode of operation, what I claim and desire to secure by Letters Patent of the United States is- 1. In apparatus of the character described, a series of cartridges adapted to be detonated, a mechanism for firing each of the cartridges, means for actuating the firing mechanism in succession comprising a weight for each mechanism, a rod for each weight on which the weight is slidable by gravity, and means for holding the weights above the firing mechanism to be actuated comprising an electro-magnet sustaining the first weight of the series on energization of its circuit and releasing the same to fall by gravity through deenergization of the same, and means whereby the fall of a weight releases a succeeding weight to the action of gravity, and means between the second and succeeding rods and respective weights therefor for retarding the speed of descent of said weights and thereby provide a definite time interval between the firing of the successive cartridges.

2. In apparatus of the character described, a series of signal elements, an actuating means for each signal element, a latch means for each signal actuating mechanism normally holding the same in inoperative position, a weight companion to each of the said actuating mechanisms, a rod for each weight on which the same is movable by gravity, said latch means having a part extending to position adjacent the lower end of the corresponding rod to be engaged and tripped by its corresponding weight to thereby release the respective actuating mechanism, means for holding the weights on the respective rods above the corresponding actuating mechanism, the rods for some of the weights having spiral grooves and the weights therefor having a part engaging the respective grooves whereby the time interval of movement from the holding means to engagement with the latch means is greater than is the case with weights on rods not provided with grooves, the holding means for each of the weights except the first of the series each having a portion in the path of movement of the preceding weight on its rod and engageable thereby in its movement by gravity to release the same whereby the weights are released to fall in succession to thereby successively actuate the latch means of the signal actuating mechanisms and release the same to actuate the corresponding signal, and an electrically controlled holding means for the first weight of the series.

JAMES E. CLARK. 

